In the aerospace industry, the use of fiber-reinforced polymer composites in primary and secondary structures of aircraft is becoming more prevalent. Composite structures are traditionally made by laying up plural layers (or plies) of resin-impregnated fibrous reinforcement (known as prepregs) on a mold surface, followed by consolidating and/or curing. The advantages of fiber-reinforced polymer composites include high strength-to-weight ratio, excellent fatigue endurance, corrosion resistance and flexibility, allowing for a significant reduction in component parts, and reducing the need for fasteners and joints. However, the application of these materials for modern aircraft's primary and secondary structures presents special challenges due to the dielectric nature of the matrix resin. Although the use of carbon fibers as reinforcing fibers in composite materials can deliver some degree of electrical conductivity along their longitudinal direction due to their graphitic nature, the dielectric properties of the matrix resins in the composite materials reduce the overall electrical conductivity of the composite materials.